My sensors were the old style that are known to be bad. So i replaced all of them, but it was still freezing the bottom on both sides. So i dug further and found that the condenser fan wasn't working so i replaced it and it's been working perfectly ever since.

Had to replace the water tank assembly (AP3189633) and all three temp sensors (AP3185407) in the unit; one on top, one in the middle and the one in the quick chill (bottom) area. Although some may have been working properly, I decided to replace all three to be sure, cheaper than calling a repair man. You may all require two union connectors (5/16"), part number AP3414915 if this is the first time repair the tank. Don't forget a six pack of beer, makes the job go easier.